ClassLoaderRepositorypublic interface ClassLoaderRepository Instances of this interface are used to keep the list of ClassLoaders
registered in an MBean Server.
They provide the necessary methods to load classes using the registered
ClassLoaders.
The first ClassLoader in a ClassLoaderRepository is
always the MBean Server's own ClassLoader.
When an MBean is registered in an MBean Server, if it is of a
subclass of {@link java.lang.ClassLoader} and if it does not
implement the interface {@link PrivateClassLoader}, it is added to
the end of the MBean Server's ClassLoaderRepository.
If it is subsequently unregistered from the MBean Server, it is
removed from the ClassLoaderRepository.
The order of MBeans in the ClassLoaderRepository is
significant. For any two MBeans X and Y in the
ClassLoaderRepository, X must appear before
Y if the registration of X was completed before
the registration of Y started. If X and
Y were registered concurrently, their order is
indeterminate. The registration of an MBean corresponds to the
call to {@link MBeanServer#registerMBean} or one of the {@link
MBeanServer}.createMBean methods. |
| Methods Summary |
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| public java.lang.Class | loadClass(java.lang.String className)Load the given class name through the list of class loaders.
Each ClassLoader in turn from the ClassLoaderRepository is
asked to load the class via its {@link
ClassLoader#loadClass(String)} method. If it successfully
returns a {@link Class} object, that is the result of this
method. If it throws a {@link ClassNotFoundException}, the
search continues with the next ClassLoader. If it throws
another exception, the exception is propagated from this
method. If the end of the list is reached, a {@link
ClassNotFoundException} is thrown.
| | public java.lang.Class | loadClassBefore(java.lang.ClassLoader stop, java.lang.String className)Load the given class name through the list of class loaders,
stopping at the given one. Each ClassLoader in turn from the
ClassLoaderRepository is asked to load the class via its {@link
ClassLoader#loadClass(String)} method. If it successfully
returns a {@link Class} object, that is the result of this
method. If it throws a {@link ClassNotFoundException}, the
search continues with the next ClassLoader. If it throws
another exception, the exception is propagated from this
method. If the search reaches stop or the end of
the list, a {@link ClassNotFoundException} is thrown.
Typically this method is called from the {@link
ClassLoader#loadClass(String) loadClass} method of
stop, to consult loaders that appear before it
in the ClassLoaderRepository. By stopping the
search as soon as stop is reached, a potential
deadlock with concurrent class loading is avoided.
| | public java.lang.Class | loadClassWithout(java.lang.ClassLoader exclude, java.lang.String className)Load the given class name through the list of class loaders,
excluding the given one. Each ClassLoader in turn from the
ClassLoaderRepository, except exclude, is asked to
load the class via its {@link ClassLoader#loadClass(String)}
method. If it successfully returns a {@link Class} object,
that is the result of this method. If it throws a {@link
ClassNotFoundException}, the search continues with the next
ClassLoader. If it throws another exception, the exception is
propagated from this method. If the end of the list is
reached, a {@link ClassNotFoundException} is thrown.
Be aware that if a ClassLoader in the ClassLoaderRepository
calls this method from its {@link ClassLoader#loadClass(String)
loadClass} method, it exposes itself to a deadlock if another
ClassLoader in the ClassLoaderRepository does the same thing at
the same time. The {@link #loadClassBefore} method is
recommended to avoid the risk of deadlock.
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